1. Field of the Invention
This invention relates to a method and system for drilling holes in ceramic and glass material. Specifically, the invention describes an abrasive drill bit that produces a smooth hole in ceramic and glass without cracking or chipping the ceramic.
It is understood that the terms “ceramic”, “tile”, “glass”, “stone” and like terms are used interchangeably as relating to this invention, which works well when drilling holes in all such similar materials. Likewise, these terms are used interchangeably when describing prior art, unless otherwise noted.
2. Related Art
There are presently two main methods of making a hole in tile: breaking and drilling.
Breaking has been the method of choice in construction, especially in plumbing installation and repair. To access plumbing, a hole is created by breaking through the tile with a small hammer and/or chisel. The best results of this method are a jagged hole; the worst results are a cracked or shattered tile that must be replaced. This technique always requires some type of cover to cover the jagged edges of the hole and to provide an air block around the hole, since a tight seal around the plumbing is difficult if not impossible. The breaking technique is not possible when dealing with crystalline structures such as glass and many crystalline stones, which will simply shatter if struck with a chisel of similar tool.
Drilling a hole into glass and tile has been possible using a diamond or carbide tipped drill bit 100, also referred to as a “tungsten arrow”, such as seen in FIG. 1A (prior art). The carbide tip 110 of carbide drill bit 100 is typically a diamond-lapped or tungsten tip that is spear shaped and able to drill through the glass. The user of carbide tipped drill bit 100 must carefully align and brace the drill that is turning the bit through the use of a special jig. This jig ensures proper alignment of the tip for drilling through the glass and with adequate pressure. Thus, drilling with carbide tipped drill bit 100 is not feasible in the field, due to this required special equipment and orientation. Another limitation of this drill bit is its expense. Another limitation is its small diameter, as standard sized carbide tipped drill bits are less than ½″ in diameter. Additionally, the finished hole produced with carbide tipped drill bit 100 usually has sharp edges, which must be smoothed off with an emery cloth or other tool, posing a cutting hazard during the smoothing off process.
To drill larger holes, such as over 1″ in diameter, in ceramic and glass material, the typical modem method in the prior art uses a diamond coated box drill bit 120, as shown in FIG B (prior art). Segment tips 125 are coated with diamond, and can cut through glass when properly aligned with a press drill. Box drill 120 must be continuously cooled during use, typically with antifreeze or other liquid capable of removing the high amounts of heat produced. Failure to do so may result in cracking of the glass and/or damage to the bit, which is expensive. While this method may be useful in a shop, such as that of a lamp maker, glass worker and the like who must drill holes in ceramic for wiring, switches, etc., it is not feasible in plumbing operations, due to the required alignment jib, mess of the coolant, etc.
It would therefore be useful improvement of the prior art for a device and method to drill holes, including large diameter (greater than 1″) holes, in glass, ceramics, tile and like materials, using a standard electric drill without a cumbersome jig.